#### Answer

Increase; $5\%$

#### Work Step by Step

It is an increase because 2100, the end amount, is greater than 2000, the original amount.
The percent change is the amount of change (the absolute value difference between the new amount and the original amount) divided by the original amount.
$\frac{2100-2000}{2000}$
We use the order of operations to solve:
First, simplify above the fraction bar with subtraction: $\frac{100}{2000}$
Next, we divide: $0.05$
To convert to a percent, we multiply by 100: $5\%$